The study design will be a single center, randomized, clinical 3-arm study, comparing the effects of an intensive lifestyle intervention based on the Look AHEAD regimen vs. a less intensive text message intervention vs. standard lifestyle advice typically provided prior to radical prostatectomy. For the control arm, participants will complete post-operative assessments at months 3, 6, 12 and 18 where they will repeat the baseline questionnaires and measures. Please note that for all recruited patients who are not local, the follow-up questionnaires will be obtained via mail, and the physical parameters will be derived from direct contact with the patient's local care provider. In the event that this is not possible, we will rely on patient self-report. Standard practice associated with surgery and postoperative laboratory testing will be performed. Patients may use a phosphodiesterase type 5 inhibitor (sildenafil, tadalafil or vardenafil) following surgery as conventional "on-demand" therapy for erectile dysfunction (ED).